This application relates to lasers, and in particular, to single-mode lasers and fiber lasers.
Various applications may require the laser wavelength of a laser to be stabilized at a specific wavelength. In optical wavelength-division-multiplexed (WDM) systems, for example, the signal wavelengths of different optical WDM channels need to be maintained at designated WDM standard wavelengths according to a wavelength standard such as the WDM wavelengths established by the International Telecommunication Union (ITU). Other applications such as spectroscopic measurements may also use stabilized lasers to excite selected atomic or molecular transitions.